1. Field of the Invention
The invention generally relates to food processing equipment, such as an electrical beverage brewer, such as a coffee or tea brewer, and, more particularly, to such food processing equipment with a plurality of manually operable function control switches for controlling the operations of the food processing apparatus.
2. Discussion of the Prior Art
Food processing equipment such as electrical coffee brewers, tea brewers, food grinders, hot water boilers, or dispensers, and the like that are electrically powered and have an operator control panel from which the operator interfaces with various operational elements of the apparatus in order to manually control the operation of the apparatus is well known. In the case of known beverage brewers, a plurality of brewer functions are respectively controlled by a plurality of associated brewer function selection switches. For instance in a single brewer, it is known to have at least one start brew cycle switch, an emergency stop brew switch, a hot water dispense switch, and full-power switch. It is also known to provide on the operator control panel a message display screen for displaying brewer status information and programming information.
When the power switch is actuated, electrical power is applied to a heating element to heat water in a hot water reservoir. After the hot water has come up to a preselected temperature and the level is at a preselected level, a brew water valve, or brew valve, is opened to pass the hot water from the hot water reservoir to a spray head. Hot water is sprayed onto the top surface of a layer of ground coffee or the like that is held within filter paper within a brew basket. The hot water passes through and dissolves some of the coffee constituents of the ground coffee during the hot water dispense period of the brew cycle to make the brewed coffee beverage. The brewed coffee passes from the brew basket into a suitable container for service or storage.
After a preselected time, corresponding to a preselected quantity of hot water and of brewed beverage, the brew valve automatically closes. The brew cycle, however, continues until the last of the hot water that was added to the brew basket passes through the coffee grounds and out of the bottom of the brew basket and into an urn or the like during the drain period, or drip period of the brew cycle.
Some of the control switches are logically disabled or have no function during different status conditions of the brewer. For instance, during the dispense period of the brew cycle, actuation of the brew cycle start switch is ineffective since the dispense valve is already open and the hot water is already being passed to the spray head. During the dispense period, the emergency stop switch, if actuated is effective to close the brew valve and stop the brew cycle. However, after the brew cycle including the drain period is concluded then actuation of the emergency stop switch has no effect because the brew cycle is already concluded, and there is nothing further to stop.
Some switches are artificially disabled at different times. For instance, when there is no brew cycle in progress, the hot water dispense switch, when manually held in an actuated state, maintains the brew valve in an open condition to pass hot water to the spray head. The brew valve remains open only so long as an operator holds the switch in an “on” state, or “open” actuated state. However, during the brew cycle drip period, there is still a filled brew basket beneath the spray head, and the hot water switch is therefore automatically disabled from reopening during this time by a brewer controller that interfaces the switches with the operating elements of the brewer.
Other brewer functions are only used rarely, but, of course, remain on the control panel and can be inadvertently actuated. Initially, during installation of a commercial brewer, after a “full power-on” switch is actuated, a fill valve is opened to fill the hot water reservoir and power is applied to the heating elements in the hot water tank to heat the water. The brewer controller places the brewer into an active state instead of a standby state. After installation, power to the heating elements is generally left on at all times including during closing hours due to relative power efficiencies of so doing versus turning the heating element power off and reheating the entire hot water tank to brew temperature each new work day.
Some brewers have the capability of making different amounts of coffee, such as one half gallon, one gallon and one and one half gallon. These different “batch quantities” have a plurality of different start brew cycle switches respectively associated with the different amounts of beverage to be brewed. Depending upon a preselected mode of operation that has been selected for the brewer, any one, any two or all three of the switches may be operational.
In the case of a mode of operation being preselected in which more than one of the start brew cycle switches is operational, the brewer controller responds to actuation of the different start brew switches by keeping the brew valve open for different dispense time periods associated with the different amounts of beverage to be brewed. However, if a brew cycle for a given quantity of beverage has been started by manual actuation of the associated one of the plurality of start brew switches, then all the other start brew switches are disabled from starting a new brew cycle for a different amount of beverage. The one brew cycle start switch that does start the brew cycle is also disabled from restarting the cycle. Upon completion of the brew cycle, then once again all of the operational brew cycle start switches are enabled.
As noted above, during initial setup, one of a plurality of different modes of operation may be selected. For instance in one mode of operation, the brewer start switches for making one half and one gallon are rendered operational so that the controller will respond to their actuation, subject to the temporary disablement during the brewing status of an existing brew cycle in progress. The third brew start switch for making one and one half gallons is rendered relatively permanently nonoperational. It will remain nonoperational until a new mode is preselected in which it is selected to be operational. Even though a switch is relatively permanently nonoperational, in known brewers, the switch remains on the operator control panel and remains visible.
While some control panels have regular push-button switches of the type that protrude through a flat rigid panel, others are known which employ a so-called touch pad assembly. The touch pad assembly employs a sheet of flexible plastic, or “touch pad” that has touch pad switches. The membrane switches are actuated by manually pressing certain switch locations of the touch pad. The touch pad is outwardly marked with the location of all the different switches beneath, and these switch locations are provided with a graphic or other indication of the function associated with the switch location. These graphics or words or letters remain visible even though the switch itself is disabled either permanently, due to disablement associated a particular mode selection, or relatively temporarily disabled in accordance with changing conditions during a brew cycle as noted above.
In the case of relatively permanently disablement, due to preselection of a mode of operation in which one or more brew start switches, or some other potentially functional capability switch, is relatively permanently disabled, it is known to provide different “touch pad” overlays for the different operational modes. The different overlays show only the switch locations of the switches that have been selected to be operational. This disadvantageously requires changing overlays in the field if there is a change in the operational capabilities or operational mode of the brewer in which different switches are rendered operational or nonoperational. In other cases, only a single overlay is used for all levels of operational capability, and all switch locations remain visible at all time even those that are relatively permanently nonoperational due to operational mode preselection.
It is also known to provide such touch pads in association with message display units that are always visible even when not being used to display a message. Often such message display units are only used during programming or during initialization to display messages and are not employed during normal operation.
Another deficiency with known food processing apparatus is that there is no tactile means for clearly indicating to a person that is visually impaired as to which function control switches are appropriate for use in general or intermittently.